Acoustic Metamaterial Ceiling for Floor Impact Sound Isolation and Measurement Methods for Reduction Performance

The impact sound isolation performance of newly constructed residential buildings has been measured and verified since 2022 to enhance sound insulation quality. The recommended impact sound isolation performance for residential buildings is set at 49 dB for tapping machine and rubber ball impact sounds. If the measured level exceeds 49 dB, corrective construction is required. Consequently, there is a growing demand for materials and methods that can effectively improve the impact sound isolation performance of existing floor impact sound insulation structures. Acoustic metamaterial ceiling materials have been developed as lightweight alternatives to conventional ceiling structures. When applied in residential units under construction with floating floor structures, these materials reduced the rubber ball impact sound level by 4 dB compared to the existing structure. Additionally, their sound reduction performance was approximately 2 dB higher than that of gypsum board finishing materials applied to conventional ceilings. Despite these advancements, there is no standardized method for quantitatively assessing the impact sound isolation performance of ceiling materials and structures in residential spaces. Based on the existing measurement methods for floor impact sound isolation performance of finishing material, KS (Korean Standard) has established a method for evaluating the impact sound reduction performance of ceiling materials.